Good morning,

A client of mine started reporting this problem about 6 months ago and
I've been trying to figure out the cause and fix it for most of that
time.

The firebird server is located on IP address xxx.xxx.xxx.xxx, with
clients located on the same ISP. The connection works just fine (a
little slow maybe) for the most part.

The problem is that the connection will mysteriously fall out from
underneth the client.

The exact error message is the client comes up with is:

ISC ERROR MESSAGE:
Unable to complete network request to host "xxx.xxx.xxx.xxx".
Error reading data from the connection.
An existing connection was forcibly closed by the remote host.

What is causing the connection to be forcibly closed? The server logs
show no message stating that it has done this or that there has been a
problem.

The server has a Dlink 604 gateway/router with NAT and the clients all
have similar configurations and all routers have the appropriate ports
opened (I've configured the server to work with 3050 and 3051
specifically). When this was first setup the connection was stable
enough to last upto 24hrs. These days it seems to be lasting less
than 3 or 4 hours.

I'm currently running FB1.5.2, because I had the need for the last
events fix using NAT'd IP addresses. The Delphi client lib I'm using
is IBO4.5x. I've even tried replacing the Dlink hardware incase of
faulty hardware.

One other note, when this was originally originally setup I was using
1.0x and IIRC everything worked a little better, but that maybe
wishfull thinking on my part.

Please if any one has some light to shed on this I would really
appreciate hearing from you.

Thanks,
Ryan.